


Mr. Fahrenheit

by yellow_crayon



Category: The Umbrella Academy (TV)
Genre: Alpha/Beta/Omega Dynamics, Bickering, Don't copy to another site, Humor, Klaus gets high from being horny, M/M, Omega Klaus Hargreeves, Poor Diego, Pseudo-Incest, Sexual Tension, Sobriety
Language: English
Status: In-Progress
Published: 2019-04-22
Updated: 2019-04-22
Packaged: 2020-01-23 08:22:17
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,158
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/18545950
Author URL: https://archiveofourown.org/users/yellow_crayon/pseuds/yellow_crayon
Summary: “The body is a temple, Diego dear,” Klaus sighs, using Diego's own words against him. He pats the alpha's cheek condescendingly, “I said I was going cold turkey, didn’t I?”“And that includes your heat suppressants and birth control too, huh?” Allison asks from the couch. “Hey, no judgment from us, you smell like fresh cookies.”(Heat highs are Klaus' new "healthy" drug of choice. No one in the family seems to mind except Diego. AU)





	Mr. Fahrenheit

**Author's Note:**

> Just finished the series on Netflix. Had to write some crack for it. Assume Luther didn't try to strangle Vanya in episode 9 and they somehow prevented the apocalypse. 
> 
> Enjoy!

“I am officially going cold turkey,” Klaus announces the morning after they prevent the apocalypse. He pauses at the head of the table, half swept into a bow as if he’s waiting for their applause.

“Atta girl,” Diego mumbles, his eyes never leaving his smartphone as he reaches out and ruffles the wrong head of hair. Vanya coughs awkwardly under his hand, her expression sympathetic as Klaus’ smile turns upside-down. Five decides to test his luck and steal a piece of toast off of Diego’s plate. He gets slapped on the back of the hand before the tips of his fingers even brush against Diego’s breakfast.

“Good for you?” Luther ventures in the silence. Diego doesn’t have to look up to hear the doubt in his voice. None of them believe Klaus, not that Diego blames them. Klaus has been in and out of rehab for the better part of a decade and nothing seems to work. But then, he’s never had any of his siblings help with the process. Diego sighs and pockets his phone. Klaus zeroes in on him the moment their eyes meet, so Diego whispers an internal prayer and beckons him over.

He breaks off a piece of toast and, ignoring Five’s murderous glare, crams it into Klaus’ mouth. “First step to getting clean is a healthy breakfast.”

 _“Yes Daddy,”_ Klaus says, long lashes fluttering sarcastically as he chews. Diego smacks him on the back of the head (he seems to be doing that a lot recently) and gets up to grab Klaus some fresh orange juice.

 

* * *

 

Luther thinks Diego has a soft spot for Klaus because he’s the only omega in the family, but technically it’s not true. Diego could care less about what his brother presented as. Klaus is his favorite brother because he’s fucking hilarious and salty af. Only Luther takes after their father's caveman mentality and sees a direct correlation between his siblings’ worth and their secondary genders. But he’s already had that fight with Luther a million times, so Diego has learned to ignore most of the rude shit that comes out of Luther’s mouth. They’re family after all and he’s trying to be better, Diego can tell. Allison is a good influence on him.

The withdraw symptoms kick in around the second day and Klaus is absolutely miserable to be around, according to Five and Luther in their text chain. Diego’s not actually there to witness it. He’s got three fights back to back and ends up calling the gym his temporary home again for the next four days. He wins in the end, and wallet bulging with enough cash to last him at least the next three months, Diego drives back to the manor.

Luther had both insisted that they all stayed after the Vanya incident, for Mom and Pogo if not for their sister. So Diego had reluctantly moved back into his old room on the third floor. He was getting tired of living in the boiler room anyway. Vanya was in her old room down the hall, Five in his on the opposite side of the house, and Luther had chosen to stick close to Allison’s room, which left Klaus free rein over the rest of the twenty or so empty rooms.

It’s nearly two in the morning when Diego walks in, hair still dripping from a post-match shower. He’s almost on the second landing when he hears the soft distressed whimpers down below. His inner alpha is instantly on alert. It’s Klaus, curled in the fetal position on the couch downstairs, a corner of his thin blanket stuffed into his mouth to drown out the noise. He almost takes out Diego’s left eye when he lays a hand on his brother’s skinny shoulder. He can feel Klaus’ bones, featherlight and delicate like a bird’s, beneath his bare skin.

“Hey, hey, it’s me, Diego!” He hisses in the darkness, putting both hands on Klaus who sags in relief. He smells like sweat and something warm and sweet, and it takes Diego’s tired mind a few seconds to realize that it’s Klaus’ natural scent underneath all the distress. He’d stopped smelling like himself after the drugs and alcohol abuse had started.

“Fuck me, I need a joint so bad, D,” Klaus’ hands are clammy and cold when they sneak underneath Diego’s shirt collar and straight for his armpits. It’s an annoying habit from their childhood, and Diego hisses at the sharp drop in temperature.

“No joints, asshole,” He snaps, swatting Klaus’ hands away, “quit it.”

“They keep calling my name, I can’t sleep,” He whines, head lolling back onto his shoulder. Even in the dim light of the living room, Diego can see the dark circles under his brother’s eyes. Klaus’ teeth gleam as he whispers, “just one, pretty please? No one else needs to know, Diego. I’ll give you a blowjob if you don’t tattle on me.”

“Jesus, Klaus,” He groans and shakes the limp figure in his arms, “don’t go around offering blowjobs to your siblings.”

“Not siblings, only you,” Klaus insists as Diego hauls him to his feet. His traitorous heart races at the words.

“You’re an idiot.” Diego's tired as hell and he really just wants to sleep. “Come on.”

“Where’re we going? Are you agreeing to the blowjob?” Klaus asks, sounding strangely excited. Diego smacks him upside the head and feels a wave of satisfaction when Klaus says “oww!”

“Shut up and follow me,” Diego says and curls his fingers firmly around Klaus’ thin wrist.

His childhood bed is not really big enough for two grown men, but Klaus somehow makes it work by pretty much plastering himself against Diego’s back. Diego’s too tired to protest when his brother presses his ice-cold toes against his warm calves and falls asleep the moment his head hits the pillow.

Klaus doesn’t scream once during the night.

 

* * *

 

It becomes a little ritual of theirs after that. Klaus even moves some of his shit over into Diego’s mostly empty closet. All his clothes are either leather or black, and sometimes both, but with Klaus’ flowery shirts, feather boas, and stolen skirts, it no longer looks like a serial killer’s wardrobe. It's more of a serial killer by day/prostitute by night situation now.

Sober Klaus is a dick. He’s also more powerful than any of them ever imagined him to be.

“Morning Sunshine,” Klaus sing-songs, waltzing into their shared bathroom one morning, buck naked and somehow already wearing two layers of mascara and glitter on his face.

Diego grunts around his toothbrush, eyes flickering to the mirror when Klaus sends one of his stolen red heels flying with a flick of a foot. He chokes on a mouthful of suds when he sees, actually sees with his own eyes, Ben standing in the doorway wearing the black hoodie he’d died in. Ben grins and gives him a cheeky five-fingered wave. Diego’s probably swallowed half of the toothpaste in his mouth by accident when he turns to Klaus for some sort of explanation.

“Sobriety, what can I say,” Klaus shrugs and tugs Diego's toothbrush out of his gaping mouth before stuffing it into his own. He throws the shower curtains closed over the alpha’s stunned face and a second later, the hot water starts running.

“See what I have to deal with on a daily basis?” Ben sighs in the silence that follows. “You should probably get a new toothbrush. Who knows where Klaus' mouth has been.”

Diego spits into the sink. “You do.”

“Exactly, and I’m telling you to buy a new toothbrush, D.”

Diego blinks.

“Klaus, you fucker.”

“Love you too, Diego,” sings Klaus.

 

* * *

 

 _“Diegooooo,”_ The demon on his back croons, _“wakey wakey!”_

And he’d been having such a nice dream. There had been pancakes and Mom, and—

“Officially one month sober, motherfuckers!” Klaus yells from his seat atop Diego’s back, punching the air with his right fist, and it’s a true testimony of how much he loves his brother that Diego doesn’t fling the knife under his pillow at Klaus’ loud face. So he just groans and attempts to mash his face deeper into the sheets.

“Oh come on, get up already.” Klaus’ fingers find his nipple ring and tugs hard.

“You are such a dick,” Diego tells him, the words muffled through three layers of sheets. Klaus just hums and bounces happily atop him. “Please tell me you’re wearing underwear and those are not your bare balls slapping against my spine, Klaus Hargreeves.”

Klaus clears his throat regally. “The purpose of wearing a skirt, dearest Diego, is that one can forgo the formality of undergarments.”

“Somebody kill me please,” Diego moans.

There’s a little celebration party in the kitchen when they eventually make their way down, Klaus flouncing down each step like a goddamn fairy and Diego hunched grumpily in his black sweatshirt and grey sweatpants. Luther, the annoying fool, has the audacity to blow a birthday whistle in his face. Diego resists the strong urge to punch the other alpha in the face as he slinks toward the corner to rest his hip against the cabinet next to Pogo and Ben. Ben's not exactly solid, and only Klaus can actually touch him, but at least they can see him now.

The girls rush over to Klaus, Allison grinning in approval over his choice of eyeliner today and Vanya smiling faintly as she gives him a one-armed hug that evolves into Klaus twirling her around the kitchen in a clumsy waltz. It’s been so long since he’s heard Vanya laugh like this and Diego finds himself smiling at their theatrics. Luther meets his gaze over their siblings’ heads and nods in approval. Diego lifts a confused eyebrow until Klaus comes to a spinning stop in front of him and he automatically reaches out to steady him. Klaus slithers down his front like Diego’s a stripper pole and throws both arms around his neck.

“I think it’s the amount of testosterone in his room,” He whispers to Ben who ducks his head and smirks.

“What?” Diego asks. Klaus pats his stubbled cheek and winks, “your sheer manliness is keeping the ghosts away, baby.”

Five snorts, his mouth stuffed full of the celebration cake Mom baked that morning. Diego growls and pinches two fingers into the exposed skin at Klaus’ hip, “get me some of that cake before Five eats it all.”

Klaus salutes him cheekily, “Anything for my sobriety genie.”

“I’m not your sobriety genie,” Diego reminds when Klaus blows him a kiss across the room.

Later that night in the privacy of his, no, it's their room now, Diego runs his thumb over the bruised purple under Klaus’ left eye and realizes that it really is just eyeshadow. The dark rings around his brother’s eyes are gone, and only then does it really hit him that Klaus is sober for the first time since forever. Diego should say something other than “wanna train together tomorrow morning?” But Klaus’ grin is blindingly bright, so he swallows whatever he’d planned to say and squeezes back when Klaus tackles him in a hug.

 

* * *

 

Diego should have known that things wouldn't be smooth sailing forever. It never is with the Hargreeves. They’re boxing in the garden when it happens.

For such a skinny guy, Klaus packs a mean punch. He’s in another one of Allison’s old skirts, black with tiny gold thunderbolts patterned into the fabric, barefooted and kohl-lined eyes gleaming as he cackles and throws another punch. Diego easily parries the blow. He’s in his element here, energy humming beneath his skin as he orders Klaus to attack again.

His brother surprises Diego by throwing his entire body at him. It’s a stupid move, but Klaus catches him by surprise and they both go down in a flurry of black fabric when Diego loses his footing.

“I win!” Klaus declares, throwing his gloves triumphantly over his shoulder.

“You cheated,” Ben corrects for him, but the words are lost to Diego. He must’ve hit his head on the way down because he’s got tunnel vision all of a sudden and everything around him seems to blur except for the droplet of sweat meandering leisurely down Klaus’ neck and over his collarbone, and Diego wants, no, needs to drag the pretty thing down and sink his teeth into—

“Hey!” Klaus yelps when Diego abruptly kicks him off and scrambles to his feet. His dick is a rigid line against the zipper of his pants, alpha instincts screaming in protest when he backs away like he’s been scalded.

“What the hell, Diego?!” Klaus shouts after him as Diego shoulders past Ben and breaks into a run.

 

* * *

 

He stays away for a while after that little incident. It had scared Diego. He hasn’t lost control like that since he was a teenager. Eerily enough, now that he thinks about it, that accident had been with Klaus as well. Funny how the brain suppresses uncomfortable memories like the time he almost mounted his omega sibling after a stressful mission.

Klaus and the others blow his phone up with text messages and calls, and for a second, Diego almost hates their new ‘caring’ family dynamic. None of them used to give a rat’s ass when he stormed out of the house and disappeared for a few weeks. But now—

Diego groans when his screen lights up again. It’s Allison this time, the caller ID a picture of her dazzling smile. Perched on a steel beam over an empty warehouse, Diego checks his watch. Two more minutes till the drug deal. He reaches for the set of knives against the right side of his ribcage and—

Someone screams outside the warehouse, high and panic-stricken. Diego almost slips from his hiding spot. He can make out the silhouette of something alien, something with long tentacle-like protrusions…fuck.

 _“Diego, where are you?”_ Klaus sings as he pushes open the door to the warehouse. His scent reaches Diego a few seconds later, and little Diego stirs in the confines of his pants. What the ever-loving fuck is happening to him?

“Diego dear, come down from there.” Shit. Is that Grace’s voice?

He yelps when Mom suddenly shines a flashlight up into the rafters and startles the nest of pigeons Diego’s hanging out with. They take flight, swatting at his head with their wings. Klaus, the callous bastard, clutches his stomach and laughs and laughs. Cursing under his breath in Spanish, Diego quickly swings down from his spot. His face is burning and he’s probably covered in feathers. Grace smiles kindly and picks a piece of straw off Diego’s head.

“Why the hell did you bring Mom?” He hisses at Klaus, infuriatingly beautiful Klaus, who is close enough to make Diego dizzy with whatever it is happening between them. He doesn’t seem to feel the same ugly attraction because Klaus giggles and lifts a shoulder in a semi-shrug, “Five said she’d be the only one to coax you out of whatever mid-life crisis slash shame spiral you’re in this week.”

“Five’s here too?” Diego groans, fisting his hair in frustration, “also, we’re the same age, douchebag.”

“Yup,” Klaus says, popping the word in his mouth, “Ben’s outside too. You should thank us for rescuing you from the big bad cartel.”

“Fuck you, Klaus, I could’ve handled it myself,” Diego says, stalking past them and trying miserably to hide his boner. He should not be this worked up with a parent present.

“We took a taxi here, babe, so we’re gonna need you to drive us back to the house,” Klaus calls gleefully after him. He gasps and links his arm through Grace’s, “should we stop for waffles, Mom?”

 

* * *

 

They do end up stopping for waffles. Five glances at the bunched leather jacket over Diego’s crotch while Klaus flirts with the dude in the drive-through window and smirks.

“Shut up and drink your milkshake,” He snaps at the little bastard and tosses his money clip at the back of Klaus’ head.

 

* * *

 

“Klaus, are you going into heat?” Luther asks the moment their pathetic little group trudge into the living room. He’s on the sofa with Allison and her feet are in his lap.

“Am I?” He giggles. In the light of the kitchen, Diego can see how big Klaus’ pupils are.

“Are you high?” Diego demands, the sudden stab of panic sharp enough to cut through the burning knot of arousal in his belly. The room smells like warm caramel and he wants to bend Klaus over the nearest surface and fuck him until he cries. Clearly, the Westermarck effect had skipped over Diego growing up because none of his other siblings seem to be hot and bothered by Klaus’ scent. Even Luther, the only other adult alpha present, seems unaffected.

“The body is a temple, Diego dear,” Klaus sighs, using his own words against him. Diego grits his teeth when his brother breezes closer, teeth gleaming and eyes black as night. He pats Diego’s cheek condescendingly, “I said I was going cold turkey, didn’t I?”

“And that included your heat suppressants and birth control too, huh?” Allison asks from the couch. “Hey, no judgment from us, you smell like fresh cookies.”

“I’m a blessing from God,” Klaus declares, twirling in his silk shawl. Diego grits his teeth and silently counts to ten inside his head.

“Pretty sure you’re high on the hormones right now,” observes Five.

“Well, aren’t you a smartypants,” Klaus coos, reaching over and pinching one of Five’s cheeks. Diego clears his throat and shuffles back into the safety of the dark hallway, “are we done here?”

“Yeah, it’s getting late,” Luther checks the clock, “way past Five’s bedtime.”

Five’s at his side in a flash, “I will stab you with this fork, Luther.”

“You can stab me tomorrow morning,” Luther gets to his feet, voice dropping back into Alpha-Mode, “after we stop the bridge bombing.”

“What bridge bombing?” Diego can’t help but ask.

“Great question, Number Two,” Luther turns to him with a curt nod, “we’re getting back together, the Umbrella Academy that is. This time plus Vanya, and you’ll be stepping in for Number Four.”

“Hey, I can help,” Klaus whines, skinny legs swinging off the edge of the kitchen table. Diego wants to eat him, and not in a cannibalistic kind of way.

“Yeah, if we infiltrate a strip joint, you’ll be the first one through the door,” Luther sighs, “no offense Klaus, just trying to protect you.”

Klaus jumps to his feet with a scowl. “No offense my ass.”

It is a fantastic ass, if Diego’s to be honest.

“You’re not the only alpha around here, Luther,” Klaus flips him off and heads for the stairs. He brushes against Diego briefly in the hallway, “you coming, D?”

Ben, who’s been standing next to Diego the whole time, glances at him critically and says, “Dude, I think he already did.”

 

tbc.

**Author's Note:**

> Comment/Kudos?


End file.
